Anti-Rho(D) IgG binds to band 3 glycoprotein of the human erythrocyte membrane.
Alkali-extracted erythrocyte ghost membranes from Rho(D)-positive and Rho(D)-negative donors were incubated with human immune anti-Rho(D) IgG and nonimmune IgG. After sensitization with IgG, the integral membrane proteins were solubilized in Brij 36T nonionic detergent and chromatographed by gel filtration. There was a distinct resolution of IgG into free and membrane-complexed forms. The IgG-complexed membrane proteins were isolated by the use of a staphylococcal protein A affinity support. The protein A-bound complexes were examined for polypeptide composition by gel electrophoresis after elution. Only Rho(D)-positive membrane proteins incubated with immune anti-Rho(D) IgG revealed intact band 3. Control Rh-negative membrane proteins that had reacted with immune anti-Rho(D) IgG and the Rh-positive membranes that had reacted with nonimmune IgG showed only low molecular weight fragments of band 3 that bound nonspecifically to IgG. Arguments are presented supporting a band 3 localization for the Rh antigen.
D001457:Anion Exchange Protein 1, Erythrocyte; D000936:Antigen-Antibody Complex; D001798:Blood Proteins; D004910:Erythrocyte Membrane / Q000032:analysis*; D004912:Erythrocytes / Q000032:analysis*; D006801:Humans; D007074:Immunoglobulin G / Q000302:isolation & purification; D008565:Membrane Proteins / Q000097:blood; D012204:Rh-Hr Blood-Group System / Q000276:immunology*
D001457:Anion Exchange Protein 1, Erythrocyte; D000936:Antigen-Antibody Complex; D001798:Blood Proteins; D007074:Immunoglobulin G; D008565:Membrane Proteins; D012204:Rh-Hr Blood-Group System